People with several clogged heart arteries fared better if they had bypass surgery rather than a less-drastic procedure in which the blood vessels are propped open with tiny mesh cylinders called stents, a study of nearly 60,000 patients found.

Those who underwent surgery were significantly more likely to survive and less likely to need repeat procedures.

However, both techniques have improved so much since the study was done that more research may be needed to determine which method works best for which patients, experts said.

The study, reported Thursday in the New England Journal of Medicine, is among the largest to compare ways of treating clogged arteries, which can lead to a heart attack.

One solution is open-heart bypass surgery, in which blood vessels are taken from another part of the body and grafted into place to create detours around blockages. A less drastic option is angioplasty and stenting, in which tiny mesh tubes are threaded into arteries to keep them flowing smoothly.

Angioplasty is often done in people with only one or two blockages, and many studies suggest that no harm is done if it is tried first, in an effort to avoid surgery, in people with multiple blockages. The new research now calls this into question.

Researchers looked at patients treated for multiple blockages in New York between 1997 and 2000. Surgery patients were 24 percent to 36 percent more likely than the others to be alive after three years.

Of those who received stents, 8 percent later needed surgery and 27 percent needed another stent procedure. Only around 5 percent of surgery patients needed a follow-up procedure.

“For people for whom there are two alternatives, bypass surgery appears to be superior,” said lead researcher Edward Hannan of the State University of New York at Albany.

In an accompanying editorial, Bernard Gersh and Dr. Robert Frye of the Mayo Clinic College of Medicine in Rochester, Minn., noted that previous studies have suggested that only diabetics did worse when given stent procedures instead of surgery.

“The implications of this study are profound and suggest that things are not as clear-cut as originally thought,” they wrote.

However, stents have improved remarkably in recent years. Unlike the plain old metal stents, the new devices are drug-coated, allowing medication to drip into blood vessels to keep them open from squeezing shut after procedures to remove blockages.

Bypass surgery also has improved. It has traditionally been performed by stopping the heart and putting the patient on a heart-lung machine. Now many patients can have so-called beating heart surgery, in which the heart continues pumping during the operation.

Very few patients got drug-coated stents or the newer bypass procedure in the New York study.

More here.